Ultra high frequency switch



t. 0, 1944- DE WITT R. GODDARD 2,360,219

ULTRA HIGH FREQUENCY SWITCH 2 Sheets-Sheet 2 Filed July 18, 1942 INVENTOR 05 W07 1?.

00A RD ATTORNEY Patented Oct. 10, 1944 ULTRA HIGH FREQUENCY SWITCH De Witt Rug: Goddard, Biverhead, N. Y., aslignor to Radio Corporation of America, a corporation of Delaware Application July is, 1942, Serial No. 451.460 (01. 200-11) 9Claims.

This invention relates to a new and useful ultra high frequency switch. which is particularly adapted for switching ultra high frequency circuits of a coaxial conductor with gas under pressure.

An object of this invention is to provide a novel and inexpensive switch, which will give low-loss operation of ultra high frequency circuits.

Another object of this invention is to provide a switch which will give a quick changeover of an ultra high frequency circuit and also to maintain the outside diameter of the inner conductor and the inside diameter of the outer conductor substantially constant.

Still another object of thi invention is to provide a switch which will be useful for switching the coaxial conductors or wave guides containing a gas under pressure, and at the same time maintaining a fluid tight Joint, good electrical shielding and uniform contact throughout.

A feature of this invention is the arrangement of a switch having a circular body portion with a rotor portion located therein, having the shape Of an inverted pyramid, which is provided with special electrical switch contact means.

The aperture in the body portion and the outer rotor portions are each accurately ground together to prevent fluid leakage.

The problem of switching ultra high frequency circuits rlmning within coaxial conductors, or wave guides with gas under pressure, is not a simple one for the reason that it is necessary to maintain a gas-tight joint and at the same time good electrical contact, good electrical shielding, uniform cross-section or impedance of the conductors and a minimum amount of lumped capacities, etc.

The system of this invention provides all of the desirable features in a relatively simple and accessible arrangement.

This invention will best be understood by referring to the accompanying drawings, in which Fig. 1 is a cross-sectional view of the complete switch;

Fig. 2 is another cross-sectional view, the section being taken at right angles to that of Fig. 1;

Fig. 3 is a plan view of Figs. 1 and 2;

Fig. 4a is a diagram showing one of the switch positions;

Fig. 4b is a diagram showing the switch in the "oil position;

Fig.4cisadiagramshowingtheswitchina position at right angles to that of Fig. 4a;

Through the central "by means of machine screw 8 Fig. 4a is a diagram showing a switchingarrangement for providing for four switch positions;

Fig. 5 is a detailed showing of the switch rotor member;

Fig. 6 is a side view, partly in section, of the fixed block member with the rotor removed;

Fig. 7 is a perspective view of one of the stationary contact members;

Fig. 8 is a cross-sectional view of another modification of the switch of this invention; and

Fig. 9 is a perspective view of Fig. 8.

Referring now in detail to Figs. 1, 2 and 3 of the drawings, the. switch is provided with a central rotor, or rotating portion, l in the form of an inverted pyramid of metal having a good electrical conductivity, which is shown in more detail in Fig. 5, and is provided with a rotatable knob la. The rotor l is arranged to rotate within a fixed circular body portion 2, also of metal, having a conical aperture arranged to receive the inverted pyramid portion of element l. The motor and aperture are to be accurately ground or fitted together to provide a gas-tight seal.

portion of rotor I two apertures lb are provided, which are both of the same diameter, and at right angles to one another, and lying in a plane normal to the axis of the cone and mid-way between its two ends. These apertures are bored out so as to intercept at the central axis.

The body portion 2 of the switch contains 3 holes 20, which are of substantially the same diameter as the apertures lb of the rotor. These holes are at right angles to one another, as shown by Fig. 3, and in such a position as to have their axes lying in the same plane as that of the apertures lb in the rotor when it is in the position as shown in Figs. Land 2. A concentric slot 6 is also provided. The rotor l is held in position within the body 2 of the switch and a slotted spring washer 1. The outer ends of the three holes 2a in the body portion 2 are slightly counter-bored at 2d to receive the ends of outer conductors 3, 4 and 5 of a coaxial conductor. The inner conductors are omitted from Figs. 1 and 2 in order to more clearly show slot 6. Located within the central portion of rotor I there is a small right angled or L-shaped conductor 9 of such size as to be passed through the apertures lb. The small conductor 9 is retained centrally in and insulated by two low- 56 loss insulators 9a. The two extreme ends of conductor 3 are shaped with knife-like portions 311 to form switch blades. The extreme length of the arms 9 are such that they do not exceed the length of the radius of cone I at the central axis of apertures Ib. This is necessary to permit assembly of rotor I, as in assembling rotor I to the body portion 2 the knife-like portions 91) must be positioned 'to line up in the three apertures 2a before rotation in slot 8. A metallic rod member ID having a slot II to receive the knife-like extremity 9b of the conductor 3.

which is supported by the rotor, is shown in detail by Fig. 7. The other end or member II is bored out with an aperture I2 to receive one 01' the inner conductors. This member III is positioned within each aperture 2a and is insulated by discs Illa. The bored-out end I! is arranged to receive or to be soldered to the ends of inner conductors 3a, 4a and 5a.

The fluid or'gas used within the concentric lines is generally air or nitrogen, with a pressure of about 15 pounds per square inch. In the special case where pipe lines carrying natural gas are to be used simultaneously as wave guides, when desired the pressure might be many hundreds of pounds per square inch. Almost any dry, non-corrosive gas would be satisfactory, such as carbon-dioxide, helium, blau gas, methane,

hydrogen sulphide, or other natural gases.

Figs. 4a, 4b, 4c and 4d show diagrammatically the four significant positions of the switch.

The diagram 4a shows terminal |2a connected to terminal Ila through right angle connector rotor Ma.

The diagram 41) shows an ofP' position, in which all three circuits are-isolated.

The diagram 40 shows terminal |2a connected to terminal I3a.

The diagram 4d shows terminal |3a connected to terminal |5a by means of member I4a.

Fig. 5 shows in detail how the right angle inner conductor 9 is located within the holes lb in the rotor 9b indicates the location of knifelike extremities of this conductor. angle conductor is held in place by low-loss insulating washers 9a, which are cemented in place within apertures lb. An alternative method of fastening in the insulators would be to use set screws 9s, as indicated in dotted lines, instead of cement.

Fig. 6 shows in detail how the outer conductors 3, 4 and 5 are arranged with members III which are provided with insulating spacing members Illa.

Fig. 7 shows a detail sketch of one of the stationary contacts III which are held within the cylindrical holes 2a in the body 2 of the switch by insulating washers Illa. The slot receives the knife-like extremity of the conductor 9, which is supported within the rotor I. The axial hole I2 is designed to act like a jack so that the inner conductor of a coaxial transmission line may be plugged into the three or four switch terminals.

In order to allow the protruding knife-like portion 91) of the inner conductor as shown in Fig. 5 to rotate within the body of the switch it is necessary to provide a concentric slot 6 as shown in Figs. 1, 2, 3 and 6. The slot 6 is made slightly larger than the knife-like portion 9b.

Figs, 8 and 9 show another arrangement in which a single-pole, 4-throw is shown. Here an inner conductor forming the input lead to the angular switch blade 4| passes axially into the conical rotor through sliding contacts. By rotat-- This right.

:ot' the transmission line.

made of some resilient material, such as berylin; the conical rotor portion 3| 'with the aid of knob II, within the stationary metallic portion 32, any of four circuits may be selected and gives tour switch positions as shown by the diagram in Fig. 4d. The inner conductor 33 of therotor I is supported by insulating washers 48., The upper portion of switch blade -4| contains a jack portion, which has a hole to receive plug 40 located on the end of the-incoming central conductor 33, which is located within the outer conductor 33, This -jack portion is lium bronze, and has several slots cut parallel to the axis in order that it will make good contact to the projection plug 40. The outer sleeve 42 is soldered to the top of the rotor and slides within the extremity 43 of the outer conductor 38 of the incoming coaxial line. This extremity 43 of the outer conductor 33 of the coaxial line is madeof resilient material and is slotted axially in order to have it make good electrical contact to the sleeve 42 when the rotor 3| is rotated. The hole 49 in the rotor 3| is bored so as to line up with hole 50 in the stator. The stationary inner conductor contacts 31 in the stator are held in position by insulating washers 48. The contacts 31 are of the same design as the one shown in Fig. 7.

The concentric slot indicated as 33 must be arranged to make suitable clearance for the extremity 45 of switch blade 4| to pass from one position to another of the various circuit positions in the stator as shown by Figs. 4a, 4b, 4c and 4d,.

Fig. 9 shows a perspective view of Fig. 8. Here 3| is the rotor, 32 is the stator whose upper circle of contact 30 is the same as that of the two conical surfaces of the rotor and stator. The outer conductor sleeves, indicated .as 33, 34 and 52, are three of the four circuit outer conductor terminals to which input switch blade 4| may be connected by rotation of the switch rotor II. The switch fixed contact 31 has a hole 35 to receive the inner conductor jack portion. The inner conductor jack portion- 53 enters into a hole 54. The lower end portion. is retained concentric by insulation washer 45. End portion 44 is knife-shaped at 48 to make contact in slot 41 of fixed contact 31.

It should be mentioned that this arrangement, using two conical switch surfaces in intimate contact, can also be used to produce a switch for selecting wave-guide circuits. The only changes necessary would be the elimination of the inner conductors and the insulating support disc, and the circular slot 6 in the stator. It would, however, be necessary to make the turn of the hole in the inner conductor as gradually as possible to reduce reflections. In Fig. 8 it would require the vertical dimensionvof the switch to be greater than that indicated in the diagram. In the switch shown in Figs. 1 to 6, inclusive, the angle between the stator circuits could be increased from 90 to and the hole or wave guide in the inner conductor follow the course of an are instead orthatof intersecting rotor to be lifted out of the switch for cleaning,

etc., without disturbing anyoi the coaxial lines running to the switch. Any suitable means for holding the rotor cone within the stator may be provided, as for example a spring-washer secured to the stationary portion.

In the operation of the embodiment shown in Figs. 1, 2, 3 the continuity of the circuit for the outer conductors is maintained by the metallic body portion 2, and it will be noted that the aperture 2a is approximately equal to that of the aperture of the inner conductors, 3, l and 5. Thus it will be noted that no switching of the outer conductor is required and there is no change in the electrical characteristic of the transmission line. The switching of the inner conductors is accomplished by having the knifelike extremities of the right angle contact member of the inner conductor I ridingin slot 8 to make contact with the slotted portion l I of members it. As will be seen in the diagram shown in Fig. 4a, a connection is made between the inner conductors Ila and 12a by the contact member a. Should it be desired to change this connection, the rotor is turned 90 degrees to the right and in this position electrical connection is made between the inner conductors Ho and lid as shown by Fig. 40. Should it be desired to entirely disconnect all of the inner conductors, the rotor I which retains contact Ila is rotated in slot I to a position between all the inner conductors which is approximately 45 degrees. This open' circuit position is diagrammatically shown in Fig. 4b.

In the operation oi the embodiment shown in .Figs. 8 and 9, the continuity of the circuit is maintained by having the extreme ends of the inner conductors secured to the metallic body portion 32, and as mentioned above the apertures within the body portion 32 are approximately similar to that of the inside diameter of the inner conductors and there is no need to switch the outer conductors. In the switching of the inner conductors of this device, input switch blade or contact member 4|, which is insulatingly supported within the rotor portion ll by means 01 insulators 48, is rotated to the desired position in slot I. The end portion 44 of contact member ll makes contact with the slot 41 of the fixed switch contacts 31. The various switching positions for this embodiment are shown in Fig. 411. An intermediate or open circuit position is accomplished by rotating rotor II approximately 45 deg ees from the position shown in Fig. 4d.

While only a few modifications or this invention are shown, it should not be limited precisely thereto.

What is claimed is:

1. An ultra high frequency switch for a gastight concentric conductor comprising a circular fixed body having apertures into which a plurality of concentric transmission lines are located, a conical aperture within said body, a plurality of contact members, insulating means for retaining said contact members within said first mentioned apertures, a conical rotor member positioned within said conical aperture, means for retaining said conical member in said conical aperture so that the side walls form a fluid-tight seal, and contacting means for electrically contacting said metallic contact members located within said first mentioned apertures to complete a circuit between adjacent contact members when said rotor is rotated.

2. A high frequency switch for a fluid-tight transmission line comprising a fixed body por- 7c tion having a plurality of apertures into which a plurality of concentric transmission line conductors are terminated, said body having a conical aperture located therein, a plurality of metallic contact members insulatingly supported within said first mentioned apertures, a rotor member positioned within saidconieal aperture, the side walls of which are arranged to be in fluid-tight engagement within inner walls of said conical aperture of the fixed body, and contact means insulatingly located within said rotor for contacting metallic members within said first mentioned apertures to complete a circuit between adjacent contact members when said rotor is rotated.

3. A high frequency switch for a fluid-tight transmission line comprising a fixed body portion having a plurality of apertures into which a plurality of concentric transmission line conductors are terminated, said body having a conical aperture located therein, a plurality of metallic contact members insulatingly supported within said first mentioned apertures, a rotor member positioned within said conical aperture, the side walls of which are arranged to be in fluid-tight engagement within inner walls of said conical aperture of the fixed body, contact means insulatingly located within said rotor for contacting metallic members within said first mentioned apertures to complete a circuit between adjacent contact memhers when said rotor is rotated, and a spring tension member secured to said rotor and having bearing means whereby said rotor is secured in gas-tight engagement with said fixed member.

4. A high frequency switch for a fluid-tight transmission line comprising a fixed metallic body portion having a plurality of apertures into which a plurality of concentric transmission line conductors are terminated, said body having a conical aperture located therein, a plurality of metallic contact members insulatingly supported within said first mentioned apertures, a rotor member positioned within said conical aperture, the side walls of which are arranged to be in fluid-tight engagement within inner walls of said conical aperture of the fixed body, an operating knob secured to said rotor, and contact means insulatingly located within apertures in said rotor for contacting metallic members within said first mentioned apertures to complete a circuit between adjacent contact members when said rotor is rotated.

5. Anultra high frequency switch comprising a fixed body portion having apertures in which a plurality of concentric line conductors are located, a conical aperture within said body, a concentric slot centrally located within said body and adjacent said conical aperture, a plurality of contact members, insulating means for retaining said contact members within said first mentioned apertures and located in a horizontal plane with respect to said fixed body portion and centrally with respect to said concentric slot, a conical member positioned within said conical aperture, contact means arranged to ride in said concentric slot, said contact means being insulatingly located within an aperture in said conical rotor member for making electrical contact with certain adjacent metallic contact members in said first mentioned apertures to complete a circuit therebetween when said rotor is rotated.

6. A high frequency switch for a fluid-tight transmission line comprising a fixed metallic disc having a plurality of apertures radially extending inward from the side wall thereof into which a tor for contacting said metallic contact members within said first mentioned apertures to complete a circuit between adjacent contact members when said rotor is rotated. I I

'I. An ultra high frequency switch for selectively connecting there different inner conductors of a concentric line comprising a fixed metallic disc having three apertures radially extending inward from the side wall thereof into which three concentric transmssion line conductors are electrically terminated, said disc having a conical aperture located therein, three contact members insulatingly located within said first mentioned apertures, a metallic conical rotor member positioned within said aperture and hav-, ing an L-shaped contact member insulatingly supported within an- Lshaped aperture in said rotor for contacting said metallic contact members which are located within said first mentioned apertures to complete a circuit between adjacent electrical contact members when said rotor is rotated.

8. An ultra high frequency switch for selectively connecting four different inner conductors,

of a concentric line comprising a fixed metallic disc having four apertures radially extending inward from the side wall thereof into which four concentric transmission line conductors are electrically terminated, a conical aperture within said disc, four contact members insulatingly located within said first mentioned apertures, a

metallic conical rotor member positioned within said conical aperture and having an L-shaped contact member insulatingly supported within an L-shaped aperture in said rotor, a concentric line centrally located on one side of said conical rotor member, the outer conductor of said line being electrically terminated by being connected to said metallic conical rotor'member, the inner conductor of said concentric line having connection means for contacting said metallic contact members which are located within said first mentioned apertures to complete an electrical circuit between said adjacent contact members when said rotor is rotated.

9. An ultra high frequency switch for selectively connecting four diiierent inner conductors of a concentric line comprising a fixed metallic disc having four apertures radially extending inward from the side wall thereof into which four concentric transmission line conductors are electrically terminated, a conical aperture within said disc, four contact members insulatingly located within said first mentioned apertures, a metallic conical rotor member positioned within said conical aperture and having an L-shaped contact member insulatingly supported within an L- shaped aperture in said rotor, a concentric line centrally located on one side of said conical rotor member, the outer conductor of said line. being electrically terminated by being connected to said metallic conical rotor member, 'an operating knob secured to said conical metallic rotor member and located at the opposite side from where the outer conductor of said concentric line is terminated, the inner conductor of said concentric line having connection means for contacting said metallic contact members which are located within said first mentioned apertures to complete an electrical circuit between said adjacent contact members when said rotor is rotated.

DE WITT RUGG GODDARD. 

